arch/x86/kvm/hyperv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * KVM Microsoft Hyper-V emulation
   4  *
   5  * derived from arch/x86/kvm/x86.c
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  * Copyright (C) 2008 Qumranet, Inc.
   9  * Copyright IBM Corporation, 2008
  10  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  11  * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
  12  *
  13  * Authors:
  14  *   Avi Kivity   <avi@qumranet.com>
  15  *   Yaniv Kamay  <yaniv@qumranet.com>
  16  *   Amit Shah    <amit.shah@qumranet.com>
  17  *   Ben-Ami Yassour <benami@il.ibm.com>
  18  *   Andrey Smetanin <asmetanin@virtuozzo.com>
  19  */
  20
  21 #include "x86.h"
  22 #include "lapic.h"
  23 #include "ioapic.h"
  24 #include "cpuid.h"
  25 #include "hyperv.h"
  26 #include "xen.h"
  27
  28 #include <linux/cpu.h>
  29 #include <linux/kvm_host.h>
  30 #include <linux/highmem.h>
  31 #include <linux/sched/cputime.h>
  32 #include <linux/eventfd.h>
  33
  34 #include <asm/apicdef.h>
  35 #include <trace/events/kvm.h>
  36
  37 #include "trace.h"
  38 #include "irq.h"
  39 #include "fpu.h"
  40
  41 /* "Hv#1" signature */
  42 #define HYPERV_CPUID_SIGNATURE_EAX 0x31237648
  43
  44 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
  45
  46 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  47                                 bool vcpu_kick);
  48
  49 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  50 {
  51         return atomic64_read(&synic->sint[sint]);
  52 }
  53
  54 static inline int synic_get_sint_vector(u64 sint_value)
  55 {
  56         if (sint_value & HV_SYNIC_SINT_MASKED)
  57                 return -1;
  58         return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  59 }
  60
  61 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  62                                       int vector)
  63 {
  64         int i;
  65
  66         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  67                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  68                         return true;
  69         }
  70         return false;
  71 }
  72
  73 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  74                                      int vector)
  75 {
  76         int i;
  77         u64 sint_value;
  78
  79         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  80                 sint_value = synic_read_sint(synic, i);
  81                 if (synic_get_sint_vector(sint_value) == vector &&
  82                     sint_value & HV_SYNIC_SINT_AUTO_EOI)
  83                         return true;
  84         }
  85         return false;
  86 }
  87
  88 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
  89                                 int vector)
  90 {
  91         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
  92         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
  93         bool auto_eoi_old, auto_eoi_new;
  94
  95         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
  96                 return;
  97
  98         if (synic_has_vector_connected(synic, vector))
  99                 __set_bit(vector, synic->vec_bitmap);
 100         else
 101                 __clear_bit(vector, synic->vec_bitmap);
 102
 103         auto_eoi_old = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 104
 105         if (synic_has_vector_auto_eoi(synic, vector))
 106                 __set_bit(vector, synic->auto_eoi_bitmap);
 107         else
 108                 __clear_bit(vector, synic->auto_eoi_bitmap);
 109
 110         auto_eoi_new = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 111
 112         if (auto_eoi_old == auto_eoi_new)
 113                 return;
 114
 115         if (!enable_apicv)
 116                 return;
 117
 118         down_write(&vcpu->kvm->arch.apicv_update_lock);
 119
 120         if (auto_eoi_new)
 121                 hv->synic_auto_eoi_used++;
 122         else
 123                 hv->synic_auto_eoi_used--;
 124
 125         /*
 126          * Inhibit APICv if any vCPU is using SynIC's AutoEOI, which relies on
 127          * the hypervisor to manually inject IRQs.
 128          */
 129         __kvm_set_or_clear_apicv_inhibit(vcpu->kvm,
 130                                          APICV_INHIBIT_REASON_HYPERV,
 131                                          !!hv->synic_auto_eoi_used);
 132
 133         up_write(&vcpu->kvm->arch.apicv_update_lock);
 134 }
 135
 136 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 137                           u64 data, bool host)
 138 {
 139         int vector, old_vector;
 140         bool masked;
 141
 142         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 143         masked = data & HV_SYNIC_SINT_MASKED;
 144
 145         /*
 146          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 147          * default '0x10000' value on boot and this should not #GP. We need to
 148          * allow zero-initing the register from host as well.
 149          */
 150         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 151                 return 1;
 152         /*
 153          * Guest may configure multiple SINTs to use the same vector, so
 154          * we maintain a bitmap of vectors handled by synic, and a
 155          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 156          * updated here, and atomically queried on fast paths.
 157          */
 158         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 159
 160         atomic64_set(&synic->sint[sint], data);
 161
 162         synic_update_vector(synic, old_vector);
 163
 164         synic_update_vector(synic, vector);
 165
 166         /* Load SynIC vectors into EOI exit bitmap */
 167         kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 168         return 0;
 169 }
 170
 171 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 172 {
 173         struct kvm_vcpu *vcpu = NULL;
 174         unsigned long i;
 175
 176         if (vpidx >= KVM_MAX_VCPUS)
 177                 return NULL;
 178
 179         vcpu = kvm_get_vcpu(kvm, vpidx);
 180         if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 181                 return vcpu;
 182         kvm_for_each_vcpu(i, vcpu, kvm)
 183                 if (kvm_hv_get_vpindex(vcpu) == vpidx)
 184                         return vcpu;
 185         return NULL;
 186 }
 187
 188 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 189 {
 190         struct kvm_vcpu *vcpu;
 191         struct kvm_vcpu_hv_synic *synic;
 192
 193         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 194         if (!vcpu || !to_hv_vcpu(vcpu))
 195                 return NULL;
 196         synic = to_hv_synic(vcpu);
 197         return (synic->active) ? synic : NULL;
 198 }
 199
 200 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 201 {
 202         struct kvm *kvm = vcpu->kvm;
 203         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 204         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 205         struct kvm_vcpu_hv_stimer *stimer;
 206         int gsi, idx;
 207
 208         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 209
 210         /* Try to deliver pending Hyper-V SynIC timers messages */
 211         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 212                 stimer = &hv_vcpu->stimer[idx];
 213                 if (stimer->msg_pending && stimer->config.enable &&
 214                     !stimer->config.direct_mode &&
 215                     stimer->config.sintx == sint)
 216                         stimer_mark_pending(stimer, false);
 217         }
 218
 219         idx = srcu_read_lock(&kvm->irq_srcu);
 220         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 221         if (gsi != -1)
 222                 kvm_notify_acked_gsi(kvm, gsi);
 223         srcu_read_unlock(&kvm->irq_srcu, idx);
 224 }
 225
 226 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 227 {
 228         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 229         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 230
 231         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 232         hv_vcpu->exit.u.synic.msr = msr;
 233         hv_vcpu->exit.u.synic.control = synic->control;
 234         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 235         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 236
 237         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 238 }
 239
 240 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 241                          u32 msr, u64 data, bool host)
 242 {
 243         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 244         int ret;
 245
 246         if (!synic->active && (!host || data))
 247                 return 1;
 248
 249         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 250
 251         ret = 0;
 252         switch (msr) {
 253         case HV_X64_MSR_SCONTROL:
 254                 synic->control = data;
 255                 if (!host)
 256                         synic_exit(synic, msr);
 257                 break;
 258         case HV_X64_MSR_SVERSION:
 259                 if (!host) {
 260                         ret = 1;
 261                         break;
 262                 }
 263                 synic->version = data;
 264                 break;
 265         case HV_X64_MSR_SIEFP:
 266                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 267                     !synic->dont_zero_synic_pages)
 268                         if (kvm_clear_guest(vcpu->kvm,
 269                                             data & PAGE_MASK, PAGE_SIZE)) {
 270                                 ret = 1;
 271                                 break;
 272                         }
 273                 synic->evt_page = data;
 274                 if (!host)
 275                         synic_exit(synic, msr);
 276                 break;
 277         case HV_X64_MSR_SIMP:
 278                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 279                     !synic->dont_zero_synic_pages)
 280                         if (kvm_clear_guest(vcpu->kvm,
 281                                             data & PAGE_MASK, PAGE_SIZE)) {
 282                                 ret = 1;
 283                                 break;
 284                         }
 285                 synic->msg_page = data;
 286                 if (!host)
 287                         synic_exit(synic, msr);
 288                 break;
 289         case HV_X64_MSR_EOM: {
 290                 int i;
 291
 292                 if (!synic->active)
 293                         break;
 294
 295                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 296                         kvm_hv_notify_acked_sint(vcpu, i);
 297                 break;
 298         }
 299         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 300                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 301                 break;
 302         default:
 303                 ret = 1;
 304                 break;
 305         }
 306         return ret;
 307 }
 308
 309 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 310 {
 311         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 312
 313         return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 314                 HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 315 }
 316
 317 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 318 {
 319         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 320
 321         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 322                 hv->hv_syndbg.control.status =
 323                         vcpu->run->hyperv.u.syndbg.status;
 324         return 1;
 325 }
 326
 327 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 328 {
 329         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 330         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 331
 332         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 333         hv_vcpu->exit.u.syndbg.msr = msr;
 334         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 335         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 336         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 337         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 338         vcpu->arch.complete_userspace_io =
 339                         kvm_hv_syndbg_complete_userspace;
 340
 341         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 342 }
 343
 344 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 345 {
 346         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 347
 348         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 349                 return 1;
 350
 351         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 352                                     to_hv_vcpu(vcpu)->vp_index, msr, data);
 353         switch (msr) {
 354         case HV_X64_MSR_SYNDBG_CONTROL:
 355                 syndbg->control.control = data;
 356                 if (!host)
 357                         syndbg_exit(vcpu, msr);
 358                 break;
 359         case HV_X64_MSR_SYNDBG_STATUS:
 360                 syndbg->control.status = data;
 361                 break;
 362         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 363                 syndbg->control.send_page = data;
 364                 break;
 365         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 366                 syndbg->control.recv_page = data;
 367                 break;
 368         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 369                 syndbg->control.pending_page = data;
 370                 if (!host)
 371                         syndbg_exit(vcpu, msr);
 372                 break;
 373         case HV_X64_MSR_SYNDBG_OPTIONS:
 374                 syndbg->options = data;
 375                 break;
 376         default:
 377                 break;
 378         }
 379
 380         return 0;
 381 }
 382
 383 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 384 {
 385         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 386
 387         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 388                 return 1;
 389
 390         switch (msr) {
 391         case HV_X64_MSR_SYNDBG_CONTROL:
 392                 *pdata = syndbg->control.control;
 393                 break;
 394         case HV_X64_MSR_SYNDBG_STATUS:
 395                 *pdata = syndbg->control.status;
 396                 break;
 397         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 398                 *pdata = syndbg->control.send_page;
 399                 break;
 400         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 401                 *pdata = syndbg->control.recv_page;
 402                 break;
 403         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 404                 *pdata = syndbg->control.pending_page;
 405                 break;
 406         case HV_X64_MSR_SYNDBG_OPTIONS:
 407                 *pdata = syndbg->options;
 408                 break;
 409         default:
 410                 break;
 411         }
 412
 413         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 414
 415         return 0;
 416 }
 417
 418 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 419                          bool host)
 420 {
 421         int ret;
 422
 423         if (!synic->active && !host)
 424                 return 1;
 425
 426         ret = 0;
 427         switch (msr) {
 428         case HV_X64_MSR_SCONTROL:
 429                 *pdata = synic->control;
 430                 break;
 431         case HV_X64_MSR_SVERSION:
 432                 *pdata = synic->version;
 433                 break;
 434         case HV_X64_MSR_SIEFP:
 435                 *pdata = synic->evt_page;
 436                 break;
 437         case HV_X64_MSR_SIMP:
 438                 *pdata = synic->msg_page;
 439                 break;
 440         case HV_X64_MSR_EOM:
 441                 *pdata = 0;
 442                 break;
 443         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 444                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 445                 break;
 446         default:
 447                 ret = 1;
 448                 break;
 449         }
 450         return ret;
 451 }
 452
 453 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 454 {
 455         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 456         struct kvm_lapic_irq irq;
 457         int ret, vector;
 458
 459         if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm))
 460                 return -EINVAL;
 461
 462         if (sint >= ARRAY_SIZE(synic->sint))
 463                 return -EINVAL;
 464
 465         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 466         if (vector < 0)
 467                 return -ENOENT;
 468
 469         memset(&irq, 0, sizeof(irq));
 470         irq.shorthand = APIC_DEST_SELF;
 471         irq.dest_mode = APIC_DEST_PHYSICAL;
 472         irq.delivery_mode = APIC_DM_FIXED;
 473         irq.vector = vector;
 474         irq.level = 1;
 475
 476         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 477         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 478         return ret;
 479 }
 480
 481 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 482 {
 483         struct kvm_vcpu_hv_synic *synic;
 484
 485         synic = synic_get(kvm, vpidx);
 486         if (!synic)
 487                 return -EINVAL;
 488
 489         return synic_set_irq(synic, sint);
 490 }
 491
 492 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 493 {
 494         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 495         int i;
 496
 497         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 498
 499         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 500                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 501                         kvm_hv_notify_acked_sint(vcpu, i);
 502 }
 503
 504 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 505 {
 506         struct kvm_vcpu_hv_synic *synic;
 507
 508         synic = synic_get(kvm, vpidx);
 509         if (!synic)
 510                 return -EINVAL;
 511
 512         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 513                 return -EINVAL;
 514
 515         atomic_set(&synic->sint_to_gsi[sint], gsi);
 516         return 0;
 517 }
 518
 519 void kvm_hv_irq_routing_update(struct kvm *kvm)
 520 {
 521         struct kvm_irq_routing_table *irq_rt;
 522         struct kvm_kernel_irq_routing_entry *e;
 523         u32 gsi;
 524
 525         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 526                                         lockdep_is_held(&kvm->irq_lock));
 527
 528         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 529                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 530                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 531                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 532                                                     e->hv_sint.sint, gsi);
 533                 }
 534         }
 535 }
 536
 537 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 538 {
 539         int i;
 540
 541         memset(synic, 0, sizeof(*synic));
 542         synic->version = HV_SYNIC_VERSION_1;
 543         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 544                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 545                 atomic_set(&synic->sint_to_gsi[i], -1);
 546         }
 547 }
 548
 549 static u64 get_time_ref_counter(struct kvm *kvm)
 550 {
 551         struct kvm_hv *hv = to_kvm_hv(kvm);
 552         struct kvm_vcpu *vcpu;
 553         u64 tsc;
 554
 555         /*
 556          * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 557          * is broken, disabled or being updated.
 558          */
 559         if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 560                 return div_u64(get_kvmclock_ns(kvm), 100);
 561
 562         vcpu = kvm_get_vcpu(kvm, 0);
 563         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 564         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 565                 + hv->tsc_ref.tsc_offset;
 566 }
 567
 568 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 569                                 bool vcpu_kick)
 570 {
 571         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 572
 573         set_bit(stimer->index,
 574                 to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 575         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 576         if (vcpu_kick)
 577                 kvm_vcpu_kick(vcpu);
 578 }
 579
 580 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 581 {
 582         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 583
 584         trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 585                                     stimer->index);
 586
 587         hrtimer_cancel(&stimer->timer);
 588         clear_bit(stimer->index,
 589                   to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 590         stimer->msg_pending = false;
 591         stimer->exp_time = 0;
 592 }
 593
 594 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 595 {
 596         struct kvm_vcpu_hv_stimer *stimer;
 597
 598         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 599         trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 600                                      stimer->index);
 601         stimer_mark_pending(stimer, true);
 602
 603         return HRTIMER_NORESTART;
 604 }
 605
 606 /*
 607  * stimer_start() assumptions:
 608  * a) stimer->count is not equal to 0
 609  * b) stimer->config has HV_STIMER_ENABLE flag
 610  */
 611 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 612 {
 613         u64 time_now;
 614         ktime_t ktime_now;
 615
 616         time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 617         ktime_now = ktime_get();
 618
 619         if (stimer->config.periodic) {
 620                 if (stimer->exp_time) {
 621                         if (time_now >= stimer->exp_time) {
 622                                 u64 remainder;
 623
 624                                 div64_u64_rem(time_now - stimer->exp_time,
 625                                               stimer->count, &remainder);
 626                                 stimer->exp_time =
 627                                         time_now + (stimer->count - remainder);
 628                         }
 629                 } else
 630                         stimer->exp_time = time_now + stimer->count;
 631
 632                 trace_kvm_hv_stimer_start_periodic(
 633                                         hv_stimer_to_vcpu(stimer)->vcpu_id,
 634                                         stimer->index,
 635                                         time_now, stimer->exp_time);
 636
 637                 hrtimer_start(&stimer->timer,
 638                               ktime_add_ns(ktime_now,
 639                                            100 * (stimer->exp_time - time_now)),
 640                               HRTIMER_MODE_ABS);
 641                 return 0;
 642         }
 643         stimer->exp_time = stimer->count;
 644         if (time_now >= stimer->count) {
 645                 /*
 646                  * Expire timer according to Hypervisor Top-Level Functional
 647                  * specification v4(15.3.1):
 648                  * "If a one shot is enabled and the specified count is in
 649                  * the past, it will expire immediately."
 650                  */
 651                 stimer_mark_pending(stimer, false);
 652                 return 0;
 653         }
 654
 655         trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 656                                            stimer->index,
 657                                            time_now, stimer->count);
 658
 659         hrtimer_start(&stimer->timer,
 660                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 661                       HRTIMER_MODE_ABS);
 662         return 0;
 663 }
 664
 665 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 666                              bool host)
 667 {
 668         union hv_stimer_config new_config = {.as_uint64 = config},
 669                 old_config = {.as_uint64 = stimer->config.as_uint64};
 670         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 671         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 672         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 673
 674         if (!synic->active && (!host || config))
 675                 return 1;
 676
 677         if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 678                      !(hv_vcpu->cpuid_cache.features_edx &
 679                        HV_STIMER_DIRECT_MODE_AVAILABLE)))
 680                 return 1;
 681
 682         trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 683                                        stimer->index, config, host);
 684
 685         stimer_cleanup(stimer);
 686         if (old_config.enable &&
 687             !new_config.direct_mode && new_config.sintx == 0)
 688                 new_config.enable = 0;
 689         stimer->config.as_uint64 = new_config.as_uint64;
 690
 691         if (stimer->config.enable)
 692                 stimer_mark_pending(stimer, false);
 693
 694         return 0;
 695 }
 696
 697 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 698                             bool host)
 699 {
 700         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 701         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 702
 703         if (!synic->active && (!host || count))
 704                 return 1;
 705
 706         trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 707                                       stimer->index, count, host);
 708
 709         stimer_cleanup(stimer);
 710         stimer->count = count;
 711         if (stimer->count == 0)
 712                 stimer->config.enable = 0;
 713         else if (stimer->config.auto_enable)
 714                 stimer->config.enable = 1;
 715
 716         if (stimer->config.enable)
 717                 stimer_mark_pending(stimer, false);
 718
 719         return 0;
 720 }
 721
 722 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 723 {
 724         *pconfig = stimer->config.as_uint64;
 725         return 0;
 726 }
 727
 728 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 729 {
 730         *pcount = stimer->count;
 731         return 0;
 732 }
 733
 734 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 735                              struct hv_message *src_msg, bool no_retry)
 736 {
 737         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 738         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 739         gfn_t msg_page_gfn;
 740         struct hv_message_header hv_hdr;
 741         int r;
 742
 743         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 744                 return -ENOENT;
 745
 746         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 747
 748         /*
 749          * Strictly following the spec-mandated ordering would assume setting
 750          * .msg_pending before checking .message_type.  However, this function
 751          * is only called in vcpu context so the entire update is atomic from
 752          * guest POV and thus the exact order here doesn't matter.
 753          */
 754         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 755                                      msg_off + offsetof(struct hv_message,
 756                                                         header.message_type),
 757                                      sizeof(hv_hdr.message_type));
 758         if (r < 0)
 759                 return r;
 760
 761         if (hv_hdr.message_type != HVMSG_NONE) {
 762                 if (no_retry)
 763                         return 0;
 764
 765                 hv_hdr.message_flags.msg_pending = 1;
 766                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 767                                               &hv_hdr.message_flags,
 768                                               msg_off +
 769                                               offsetof(struct hv_message,
 770                                                        header.message_flags),
 771                                               sizeof(hv_hdr.message_flags));
 772                 if (r < 0)
 773                         return r;
 774                 return -EAGAIN;
 775         }
 776
 777         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 778                                       sizeof(src_msg->header) +
 779                                       src_msg->header.payload_size);
 780         if (r < 0)
 781                 return r;
 782
 783         r = synic_set_irq(synic, sint);
 784         if (r < 0)
 785                 return r;
 786         if (r == 0)
 787                 return -EFAULT;
 788         return 0;
 789 }
 790
 791 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 792 {
 793         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 794         struct hv_message *msg = &stimer->msg;
 795         struct hv_timer_message_payload *payload =
 796                         (struct hv_timer_message_payload *)&msg->u.payload;
 797
 798         /*
 799          * To avoid piling up periodic ticks, don't retry message
 800          * delivery for them (within "lazy" lost ticks policy).
 801          */
 802         bool no_retry = stimer->config.periodic;
 803
 804         payload->expiration_time = stimer->exp_time;
 805         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 806         return synic_deliver_msg(to_hv_synic(vcpu),
 807                                  stimer->config.sintx, msg,
 808                                  no_retry);
 809 }
 810
 811 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 812 {
 813         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 814         struct kvm_lapic_irq irq = {
 815                 .delivery_mode = APIC_DM_FIXED,
 816                 .vector = stimer->config.apic_vector
 817         };
 818
 819         if (lapic_in_kernel(vcpu))
 820                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 821         return 0;
 822 }
 823
 824 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 825 {
 826         int r, direct = stimer->config.direct_mode;
 827
 828         stimer->msg_pending = true;
 829         if (!direct)
 830                 r = stimer_send_msg(stimer);
 831         else
 832                 r = stimer_notify_direct(stimer);
 833         trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 834                                        stimer->index, direct, r);
 835         if (!r) {
 836                 stimer->msg_pending = false;
 837                 if (!(stimer->config.periodic))
 838                         stimer->config.enable = 0;
 839         }
 840 }
 841
 842 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 843 {
 844         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 845         struct kvm_vcpu_hv_stimer *stimer;
 846         u64 time_now, exp_time;
 847         int i;
 848
 849         if (!hv_vcpu)
 850                 return;
 851
 852         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 853                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 854                         stimer = &hv_vcpu->stimer[i];
 855                         if (stimer->config.enable) {
 856                                 exp_time = stimer->exp_time;
 857
 858                                 if (exp_time) {
 859                                         time_now =
 860                                                 get_time_ref_counter(vcpu->kvm);
 861                                         if (time_now >= exp_time)
 862                                                 stimer_expiration(stimer);
 863                                 }
 864
 865                                 if ((stimer->config.enable) &&
 866                                     stimer->count) {
 867                                         if (!stimer->msg_pending)
 868                                                 stimer_start(stimer);
 869                                 } else
 870                                         stimer_cleanup(stimer);
 871                         }
 872                 }
 873 }
 874
 875 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 876 {
 877         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 878         int i;
 879
 880         if (!hv_vcpu)
 881                 return;
 882
 883         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 884                 stimer_cleanup(&hv_vcpu->stimer[i]);
 885
 886         kfree(hv_vcpu);
 887         vcpu->arch.hyperv = NULL;
 888 }
 889
 890 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 891 {
 892         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 893
 894         if (!hv_vcpu)
 895                 return false;
 896
 897         if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 898                 return false;
 899         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 900 }
 901 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 902
 903 bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
 904                             struct hv_vp_assist_page *assist_page)
 905 {
 906         if (!kvm_hv_assist_page_enabled(vcpu))
 907                 return false;
 908         return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 909                                       assist_page, sizeof(*assist_page));
 910 }
 911 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 912
 913 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 914 {
 915         struct hv_message *msg = &stimer->msg;
 916         struct hv_timer_message_payload *payload =
 917                         (struct hv_timer_message_payload *)&msg->u.payload;
 918
 919         memset(&msg->header, 0, sizeof(msg->header));
 920         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 921         msg->header.payload_size = sizeof(*payload);
 922
 923         payload->timer_index = stimer->index;
 924         payload->expiration_time = 0;
 925         payload->delivery_time = 0;
 926 }
 927
 928 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 929 {
 930         memset(stimer, 0, sizeof(*stimer));
 931         stimer->index = timer_index;
 932         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 933         stimer->timer.function = stimer_timer_callback;
 934         stimer_prepare_msg(stimer);
 935 }
 936
 937 static int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 938 {
 939         struct kvm_vcpu_hv *hv_vcpu;
 940         int i;
 941
 942         hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 943         if (!hv_vcpu)
 944                 return -ENOMEM;
 945
 946         vcpu->arch.hyperv = hv_vcpu;
 947         hv_vcpu->vcpu = vcpu;
 948
 949         synic_init(&hv_vcpu->synic);
 950
 951         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 952         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 953                 stimer_init(&hv_vcpu->stimer[i], i);
 954
 955         hv_vcpu->vp_index = vcpu->vcpu_idx;
 956
 957         return 0;
 958 }
 959
 960 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 961 {
 962         struct kvm_vcpu_hv_synic *synic;
 963         int r;
 964
 965         if (!to_hv_vcpu(vcpu)) {
 966                 r = kvm_hv_vcpu_init(vcpu);
 967                 if (r)
 968                         return r;
 969         }
 970
 971         synic = to_hv_synic(vcpu);
 972
 973         synic->active = true;
 974         synic->dont_zero_synic_pages = dont_zero_synic_pages;
 975         synic->control = HV_SYNIC_CONTROL_ENABLE;
 976         return 0;
 977 }
 978
 979 static bool kvm_hv_msr_partition_wide(u32 msr)
 980 {
 981         bool r = false;
 982
 983         switch (msr) {
 984         case HV_X64_MSR_GUEST_OS_ID:
 985         case HV_X64_MSR_HYPERCALL:
 986         case HV_X64_MSR_REFERENCE_TSC:
 987         case HV_X64_MSR_TIME_REF_COUNT:
 988         case HV_X64_MSR_CRASH_CTL:
 989         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 990         case HV_X64_MSR_RESET:
 991         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
 992         case HV_X64_MSR_TSC_EMULATION_CONTROL:
 993         case HV_X64_MSR_TSC_EMULATION_STATUS:
 994         case HV_X64_MSR_SYNDBG_OPTIONS:
 995         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 996                 r = true;
 997                 break;
 998         }
 999
1000         return r;
1001 }
1002
1003 static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
1004 {
1005         struct kvm_hv *hv = to_kvm_hv(kvm);
1006         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1007
1008         if (WARN_ON_ONCE(index >= size))
1009                 return -EINVAL;
1010
1011         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
1012         return 0;
1013 }
1014
1015 static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
1016 {
1017         struct kvm_hv *hv = to_kvm_hv(kvm);
1018
1019         *pdata = hv->hv_crash_ctl;
1020         return 0;
1021 }
1022
1023 static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
1024 {
1025         struct kvm_hv *hv = to_kvm_hv(kvm);
1026
1027         hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
1028
1029         return 0;
1030 }
1031
1032 static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1033 {
1034         struct kvm_hv *hv = to_kvm_hv(kvm);
1035         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1036
1037         if (WARN_ON_ONCE(index >= size))
1038                 return -EINVAL;
1039
1040         hv->hv_crash_param[array_index_nospec(index, size)] = data;
1041         return 0;
1042 }
1043
1044 /*
1045  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1046  * between them is possible:
1047  *
1048  * kvmclock formula:
1049  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1050  *           + system_time
1051  *
1052  * Hyper-V formula:
1053  *    nsec/100 = ticks * scale / 2^64 + offset
1054  *
1055  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1056  * By dividing the kvmclock formula by 100 and equating what's left we get:
1057  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1058  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1059  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1060  *
1061  * Now expand the kvmclock formula and divide by 100:
1062  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1063  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1064  *           + system_time
1065  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1066  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1067  *               + system_time / 100
1068  *
1069  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1070  *    nsec/100 = ticks * scale / 2^64
1071  *               - tsc_timestamp * scale / 2^64
1072  *               + system_time / 100
1073  *
1074  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1075  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1076  *
1077  * These two equivalencies are implemented in this function.
1078  */
1079 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1080                                         struct ms_hyperv_tsc_page *tsc_ref)
1081 {
1082         u64 max_mul;
1083
1084         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1085                 return false;
1086
1087         /*
1088          * check if scale would overflow, if so we use the time ref counter
1089          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1090          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1091          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1092          */
1093         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1094         if (hv_clock->tsc_to_system_mul >= max_mul)
1095                 return false;
1096
1097         /*
1098          * Otherwise compute the scale and offset according to the formulas
1099          * derived above.
1100          */
1101         tsc_ref->tsc_scale =
1102                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1103                                 hv_clock->tsc_to_system_mul,
1104                                 100);
1105
1106         tsc_ref->tsc_offset = hv_clock->system_time;
1107         do_div(tsc_ref->tsc_offset, 100);
1108         tsc_ref->tsc_offset -=
1109                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1110         return true;
1111 }
1112
1113 /*
1114  * Don't touch TSC page values if the guest has opted for TSC emulation after
1115  * migration. KVM doesn't fully support reenlightenment notifications and TSC
1116  * access emulation and Hyper-V is known to expect the values in TSC page to
1117  * stay constant before TSC access emulation is disabled from guest side
1118  * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1119  * frequency and guest visible TSC value across migration (and prevent it when
1120  * TSC scaling is unsupported).
1121  */
1122 static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1123 {
1124         return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1125                 hv->hv_tsc_emulation_control;
1126 }
1127
1128 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1129                            struct pvclock_vcpu_time_info *hv_clock)
1130 {
1131         struct kvm_hv *hv = to_kvm_hv(kvm);
1132         u32 tsc_seq;
1133         u64 gfn;
1134
1135         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1136         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1137
1138         mutex_lock(&hv->hv_lock);
1139
1140         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1141             hv->hv_tsc_page_status == HV_TSC_PAGE_SET ||
1142             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1143                 goto out_unlock;
1144
1145         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1146                 goto out_unlock;
1147
1148         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1149         /*
1150          * Because the TSC parameters only vary when there is a
1151          * change in the master clock, do not bother with caching.
1152          */
1153         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1154                                     &tsc_seq, sizeof(tsc_seq))))
1155                 goto out_err;
1156
1157         if (tsc_seq && tsc_page_update_unsafe(hv)) {
1158                 if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1159                         goto out_err;
1160
1161                 hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1162                 goto out_unlock;
1163         }
1164
1165         /*
1166          * While we're computing and writing the parameters, force the
1167          * guest to use the time reference count MSR.
1168          */
1169         hv->tsc_ref.tsc_sequence = 0;
1170         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1171                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1172                 goto out_err;
1173
1174         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1175                 goto out_err;
1176
1177         /* Ensure sequence is zero before writing the rest of the struct.  */
1178         smp_wmb();
1179         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1180                 goto out_err;
1181
1182         /*
1183          * Now switch to the TSC page mechanism by writing the sequence.
1184          */
1185         tsc_seq++;
1186         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1187                 tsc_seq = 1;
1188
1189         /* Write the struct entirely before the non-zero sequence.  */
1190         smp_wmb();
1191
1192         hv->tsc_ref.tsc_sequence = tsc_seq;
1193         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1194                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1195                 goto out_err;
1196
1197         hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1198         goto out_unlock;
1199
1200 out_err:
1201         hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1202 out_unlock:
1203         mutex_unlock(&hv->hv_lock);
1204 }
1205
1206 void kvm_hv_request_tsc_page_update(struct kvm *kvm)
1207 {
1208         struct kvm_hv *hv = to_kvm_hv(kvm);
1209
1210         mutex_lock(&hv->hv_lock);
1211
1212         if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET &&
1213             !tsc_page_update_unsafe(hv))
1214                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1215
1216         mutex_unlock(&hv->hv_lock);
1217 }
1218
1219 static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1220 {
1221         if (!hv_vcpu->enforce_cpuid)
1222                 return true;
1223
1224         switch (msr) {
1225         case HV_X64_MSR_GUEST_OS_ID:
1226         case HV_X64_MSR_HYPERCALL:
1227                 return hv_vcpu->cpuid_cache.features_eax &
1228                         HV_MSR_HYPERCALL_AVAILABLE;
1229         case HV_X64_MSR_VP_RUNTIME:
1230                 return hv_vcpu->cpuid_cache.features_eax &
1231                         HV_MSR_VP_RUNTIME_AVAILABLE;
1232         case HV_X64_MSR_TIME_REF_COUNT:
1233                 return hv_vcpu->cpuid_cache.features_eax &
1234                         HV_MSR_TIME_REF_COUNT_AVAILABLE;
1235         case HV_X64_MSR_VP_INDEX:
1236                 return hv_vcpu->cpuid_cache.features_eax &
1237                         HV_MSR_VP_INDEX_AVAILABLE;
1238         case HV_X64_MSR_RESET:
1239                 return hv_vcpu->cpuid_cache.features_eax &
1240                         HV_MSR_RESET_AVAILABLE;
1241         case HV_X64_MSR_REFERENCE_TSC:
1242                 return hv_vcpu->cpuid_cache.features_eax &
1243                         HV_MSR_REFERENCE_TSC_AVAILABLE;
1244         case HV_X64_MSR_SCONTROL:
1245         case HV_X64_MSR_SVERSION:
1246         case HV_X64_MSR_SIEFP:
1247         case HV_X64_MSR_SIMP:
1248         case HV_X64_MSR_EOM:
1249         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1250                 return hv_vcpu->cpuid_cache.features_eax &
1251                         HV_MSR_SYNIC_AVAILABLE;
1252         case HV_X64_MSR_STIMER0_CONFIG:
1253         case HV_X64_MSR_STIMER1_CONFIG:
1254         case HV_X64_MSR_STIMER2_CONFIG:
1255         case HV_X64_MSR_STIMER3_CONFIG:
1256         case HV_X64_MSR_STIMER0_COUNT:
1257         case HV_X64_MSR_STIMER1_COUNT:
1258         case HV_X64_MSR_STIMER2_COUNT:
1259         case HV_X64_MSR_STIMER3_COUNT:
1260                 return hv_vcpu->cpuid_cache.features_eax &
1261                         HV_MSR_SYNTIMER_AVAILABLE;
1262         case HV_X64_MSR_EOI:
1263         case HV_X64_MSR_ICR:
1264         case HV_X64_MSR_TPR:
1265         case HV_X64_MSR_VP_ASSIST_PAGE:
1266                 return hv_vcpu->cpuid_cache.features_eax &
1267                         HV_MSR_APIC_ACCESS_AVAILABLE;
1268                 break;
1269         case HV_X64_MSR_TSC_FREQUENCY:
1270         case HV_X64_MSR_APIC_FREQUENCY:
1271                 return hv_vcpu->cpuid_cache.features_eax &
1272                         HV_ACCESS_FREQUENCY_MSRS;
1273         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1274         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1275         case HV_X64_MSR_TSC_EMULATION_STATUS:
1276                 return hv_vcpu->cpuid_cache.features_eax &
1277                         HV_ACCESS_REENLIGHTENMENT;
1278         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1279         case HV_X64_MSR_CRASH_CTL:
1280                 return hv_vcpu->cpuid_cache.features_edx &
1281                         HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1282         case HV_X64_MSR_SYNDBG_OPTIONS:
1283         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1284                 return hv_vcpu->cpuid_cache.features_edx &
1285                         HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1286         default:
1287                 break;
1288         }
1289
1290         return false;
1291 }
1292
1293 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1294                              bool host)
1295 {
1296         struct kvm *kvm = vcpu->kvm;
1297         struct kvm_hv *hv = to_kvm_hv(kvm);
1298
1299         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1300                 return 1;
1301
1302         switch (msr) {
1303         case HV_X64_MSR_GUEST_OS_ID:
1304                 hv->hv_guest_os_id = data;
1305                 /* setting guest os id to zero disables hypercall page */
1306                 if (!hv->hv_guest_os_id)
1307                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1308                 break;
1309         case HV_X64_MSR_HYPERCALL: {
1310                 u8 instructions[9];
1311                 int i = 0;
1312                 u64 addr;
1313
1314                 /* if guest os id is not set hypercall should remain disabled */
1315                 if (!hv->hv_guest_os_id)
1316                         break;
1317                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1318                         hv->hv_hypercall = data;
1319                         break;
1320                 }
1321
1322                 /*
1323                  * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1324                  * the same way Xen itself does, by setting the bit 31 of EAX
1325                  * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1326                  * going to be clobbered on 64-bit.
1327                  */
1328                 if (kvm_xen_hypercall_enabled(kvm)) {
1329                         /* orl $0x80000000, %eax */
1330                         instructions[i++] = 0x0d;
1331                         instructions[i++] = 0x00;
1332                         instructions[i++] = 0x00;
1333                         instructions[i++] = 0x00;
1334                         instructions[i++] = 0x80;
1335                 }
1336
1337                 /* vmcall/vmmcall */
1338                 static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i);
1339                 i += 3;
1340
1341                 /* ret */
1342                 ((unsigned char *)instructions)[i++] = 0xc3;
1343
1344                 addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1345                 if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1346                         return 1;
1347                 hv->hv_hypercall = data;
1348                 break;
1349         }
1350         case HV_X64_MSR_REFERENCE_TSC:
1351                 hv->hv_tsc_page = data;
1352                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1353                         if (!host)
1354                                 hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1355                         else
1356                                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1357                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1358                 } else {
1359                         hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1360                 }
1361                 break;
1362         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1363                 return kvm_hv_msr_set_crash_data(kvm,
1364                                                  msr - HV_X64_MSR_CRASH_P0,
1365                                                  data);
1366         case HV_X64_MSR_CRASH_CTL:
1367                 if (host)
1368                         return kvm_hv_msr_set_crash_ctl(kvm, data);
1369
1370                 if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1371                         vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1372                                    hv->hv_crash_param[0],
1373                                    hv->hv_crash_param[1],
1374                                    hv->hv_crash_param[2],
1375                                    hv->hv_crash_param[3],
1376                                    hv->hv_crash_param[4]);
1377
1378                         /* Send notification about crash to user space */
1379                         kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1380                 }
1381                 break;
1382         case HV_X64_MSR_RESET:
1383                 if (data == 1) {
1384                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1385                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1386                 }
1387                 break;
1388         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1389                 hv->hv_reenlightenment_control = data;
1390                 break;
1391         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1392                 hv->hv_tsc_emulation_control = data;
1393                 break;
1394         case HV_X64_MSR_TSC_EMULATION_STATUS:
1395                 if (data && !host)
1396                         return 1;
1397
1398                 hv->hv_tsc_emulation_status = data;
1399                 break;
1400         case HV_X64_MSR_TIME_REF_COUNT:
1401                 /* read-only, but still ignore it if host-initiated */
1402                 if (!host)
1403                         return 1;
1404                 break;
1405         case HV_X64_MSR_SYNDBG_OPTIONS:
1406         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1407                 return syndbg_set_msr(vcpu, msr, data, host);
1408         default:
1409                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1410                             msr, data);
1411                 return 1;
1412         }
1413         return 0;
1414 }
1415
1416 /* Calculate cpu time spent by current task in 100ns units */
1417 static u64 current_task_runtime_100ns(void)
1418 {
1419         u64 utime, stime;
1420
1421         task_cputime_adjusted(current, &utime, &stime);
1422
1423         return div_u64(utime + stime, 100);
1424 }
1425
1426 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1427 {
1428         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1429
1430         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1431                 return 1;
1432
1433         switch (msr) {
1434         case HV_X64_MSR_VP_INDEX: {
1435                 struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1436                 u32 new_vp_index = (u32)data;
1437
1438                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1439                         return 1;
1440
1441                 if (new_vp_index == hv_vcpu->vp_index)
1442                         return 0;
1443
1444                 /*
1445                  * The VP index is initialized to vcpu_index by
1446                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1447                  * VP index is changing, adjust num_mismatched_vp_indexes if
1448                  * it now matches or no longer matches vcpu_idx.
1449                  */
1450                 if (hv_vcpu->vp_index == vcpu->vcpu_idx)
1451                         atomic_inc(&hv->num_mismatched_vp_indexes);
1452                 else if (new_vp_index == vcpu->vcpu_idx)
1453                         atomic_dec(&hv->num_mismatched_vp_indexes);
1454
1455                 hv_vcpu->vp_index = new_vp_index;
1456                 break;
1457         }
1458         case HV_X64_MSR_VP_ASSIST_PAGE: {
1459                 u64 gfn;
1460                 unsigned long addr;
1461
1462                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1463                         hv_vcpu->hv_vapic = data;
1464                         if (kvm_lapic_set_pv_eoi(vcpu, 0, 0))
1465                                 return 1;
1466                         break;
1467                 }
1468                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1469                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1470                 if (kvm_is_error_hva(addr))
1471                         return 1;
1472
1473                 /*
1474                  * Clear apic_assist portion of struct hv_vp_assist_page
1475                  * only, there can be valuable data in the rest which needs
1476                  * to be preserved e.g. on migration.
1477                  */
1478                 if (__put_user(0, (u32 __user *)addr))
1479                         return 1;
1480                 hv_vcpu->hv_vapic = data;
1481                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1482                 if (kvm_lapic_set_pv_eoi(vcpu,
1483                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1484                                             sizeof(struct hv_vp_assist_page)))
1485                         return 1;
1486                 break;
1487         }
1488         case HV_X64_MSR_EOI:
1489                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1490         case HV_X64_MSR_ICR:
1491                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1492         case HV_X64_MSR_TPR:
1493                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1494         case HV_X64_MSR_VP_RUNTIME:
1495                 if (!host)
1496                         return 1;
1497                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1498                 break;
1499         case HV_X64_MSR_SCONTROL:
1500         case HV_X64_MSR_SVERSION:
1501         case HV_X64_MSR_SIEFP:
1502         case HV_X64_MSR_SIMP:
1503         case HV_X64_MSR_EOM:
1504         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1505                 return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1506         case HV_X64_MSR_STIMER0_CONFIG:
1507         case HV_X64_MSR_STIMER1_CONFIG:
1508         case HV_X64_MSR_STIMER2_CONFIG:
1509         case HV_X64_MSR_STIMER3_CONFIG: {
1510                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1511
1512                 return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1513                                          data, host);
1514         }
1515         case HV_X64_MSR_STIMER0_COUNT:
1516         case HV_X64_MSR_STIMER1_COUNT:
1517         case HV_X64_MSR_STIMER2_COUNT:
1518         case HV_X64_MSR_STIMER3_COUNT: {
1519                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1520
1521                 return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1522                                         data, host);
1523         }
1524         case HV_X64_MSR_TSC_FREQUENCY:
1525         case HV_X64_MSR_APIC_FREQUENCY:
1526                 /* read-only, but still ignore it if host-initiated */
1527                 if (!host)
1528                         return 1;
1529                 break;
1530         default:
1531                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1532                             msr, data);
1533                 return 1;
1534         }
1535
1536         return 0;
1537 }
1538
1539 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1540                              bool host)
1541 {
1542         u64 data = 0;
1543         struct kvm *kvm = vcpu->kvm;
1544         struct kvm_hv *hv = to_kvm_hv(kvm);
1545
1546         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1547                 return 1;
1548
1549         switch (msr) {
1550         case HV_X64_MSR_GUEST_OS_ID:
1551                 data = hv->hv_guest_os_id;
1552                 break;
1553         case HV_X64_MSR_HYPERCALL:
1554                 data = hv->hv_hypercall;
1555                 break;
1556         case HV_X64_MSR_TIME_REF_COUNT:
1557                 data = get_time_ref_counter(kvm);
1558                 break;
1559         case HV_X64_MSR_REFERENCE_TSC:
1560                 data = hv->hv_tsc_page;
1561                 break;
1562         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1563                 return kvm_hv_msr_get_crash_data(kvm,
1564                                                  msr - HV_X64_MSR_CRASH_P0,
1565                                                  pdata);
1566         case HV_X64_MSR_CRASH_CTL:
1567                 return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1568         case HV_X64_MSR_RESET:
1569                 data = 0;
1570                 break;
1571         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1572                 data = hv->hv_reenlightenment_control;
1573                 break;
1574         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1575                 data = hv->hv_tsc_emulation_control;
1576                 break;
1577         case HV_X64_MSR_TSC_EMULATION_STATUS:
1578                 data = hv->hv_tsc_emulation_status;
1579                 break;
1580         case HV_X64_MSR_SYNDBG_OPTIONS:
1581         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1582                 return syndbg_get_msr(vcpu, msr, pdata, host);
1583         default:
1584                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1585                 return 1;
1586         }
1587
1588         *pdata = data;
1589         return 0;
1590 }
1591
1592 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1593                           bool host)
1594 {
1595         u64 data = 0;
1596         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1597
1598         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1599                 return 1;
1600
1601         switch (msr) {
1602         case HV_X64_MSR_VP_INDEX:
1603                 data = hv_vcpu->vp_index;
1604                 break;
1605         case HV_X64_MSR_EOI:
1606                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1607         case HV_X64_MSR_ICR:
1608                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1609         case HV_X64_MSR_TPR:
1610                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1611         case HV_X64_MSR_VP_ASSIST_PAGE:
1612                 data = hv_vcpu->hv_vapic;
1613                 break;
1614         case HV_X64_MSR_VP_RUNTIME:
1615                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1616                 break;
1617         case HV_X64_MSR_SCONTROL:
1618         case HV_X64_MSR_SVERSION:
1619         case HV_X64_MSR_SIEFP:
1620         case HV_X64_MSR_SIMP:
1621         case HV_X64_MSR_EOM:
1622         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1623                 return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1624         case HV_X64_MSR_STIMER0_CONFIG:
1625         case HV_X64_MSR_STIMER1_CONFIG:
1626         case HV_X64_MSR_STIMER2_CONFIG:
1627         case HV_X64_MSR_STIMER3_CONFIG: {
1628                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1629
1630                 return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1631                                          pdata);
1632         }
1633         case HV_X64_MSR_STIMER0_COUNT:
1634         case HV_X64_MSR_STIMER1_COUNT:
1635         case HV_X64_MSR_STIMER2_COUNT:
1636         case HV_X64_MSR_STIMER3_COUNT: {
1637                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1638
1639                 return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1640                                         pdata);
1641         }
1642         case HV_X64_MSR_TSC_FREQUENCY:
1643                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1644                 break;
1645         case HV_X64_MSR_APIC_FREQUENCY:
1646                 data = APIC_BUS_FREQUENCY;
1647                 break;
1648         default:
1649                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1650                 return 1;
1651         }
1652         *pdata = data;
1653         return 0;
1654 }
1655
1656 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1657 {
1658         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1659
1660         if (!host && !vcpu->arch.hyperv_enabled)
1661                 return 1;
1662
1663         if (!to_hv_vcpu(vcpu)) {
1664                 if (kvm_hv_vcpu_init(vcpu))
1665                         return 1;
1666         }
1667
1668         if (kvm_hv_msr_partition_wide(msr)) {
1669                 int r;
1670
1671                 mutex_lock(&hv->hv_lock);
1672                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1673                 mutex_unlock(&hv->hv_lock);
1674                 return r;
1675         } else
1676                 return kvm_hv_set_msr(vcpu, msr, data, host);
1677 }
1678
1679 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1680 {
1681         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1682
1683         if (!host && !vcpu->arch.hyperv_enabled)
1684                 return 1;
1685
1686         if (!to_hv_vcpu(vcpu)) {
1687                 if (kvm_hv_vcpu_init(vcpu))
1688                         return 1;
1689         }
1690
1691         if (kvm_hv_msr_partition_wide(msr)) {
1692                 int r;
1693
1694                 mutex_lock(&hv->hv_lock);
1695                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1696                 mutex_unlock(&hv->hv_lock);
1697                 return r;
1698         } else
1699                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1700 }
1701
1702 static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
1703                                     u64 valid_bank_mask, unsigned long *vcpu_mask)
1704 {
1705         struct kvm_hv *hv = to_kvm_hv(kvm);
1706         bool has_mismatch = atomic_read(&hv->num_mismatched_vp_indexes);
1707         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1708         struct kvm_vcpu *vcpu;
1709         int bank, sbank = 0;
1710         unsigned long i;
1711         u64 *bitmap;
1712
1713         BUILD_BUG_ON(sizeof(vp_bitmap) >
1714                      sizeof(*vcpu_mask) * BITS_TO_LONGS(KVM_MAX_VCPUS));
1715
1716         /*
1717          * If vp_index == vcpu_idx for all vCPUs, fill vcpu_mask directly, else
1718          * fill a temporary buffer and manually test each vCPU's VP index.
1719          */
1720         if (likely(!has_mismatch))
1721                 bitmap = (u64 *)vcpu_mask;
1722         else
1723                 bitmap = vp_bitmap;
1724
1725         /*
1726          * Each set of 64 VPs is packed into sparse_banks, with valid_bank_mask
1727          * having a '1' for each bank that exists in sparse_banks.  Sets must
1728          * be in ascending order, i.e. bank0..bankN.
1729          */
1730         memset(bitmap, 0, sizeof(vp_bitmap));
1731         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1732                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1733                 bitmap[bank] = sparse_banks[sbank++];
1734
1735         if (likely(!has_mismatch))
1736                 return;
1737
1738         bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
1739         kvm_for_each_vcpu(i, vcpu, kvm) {
1740                 if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1741                         __set_bit(i, vcpu_mask);
1742         }
1743 }
1744
1745 struct kvm_hv_hcall {
1746         u64 param;
1747         u64 ingpa;
1748         u64 outgpa;
1749         u16 code;
1750         u16 var_cnt;
1751         u16 rep_cnt;
1752         u16 rep_idx;
1753         bool fast;
1754         bool rep;
1755         sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1756 };
1757
1758 static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
1759                                  int consumed_xmm_halves,
1760                                  u64 *sparse_banks, gpa_t offset)
1761 {
1762         u16 var_cnt;
1763         int i;
1764
1765         if (hc->var_cnt > 64)
1766                 return -EINVAL;
1767
1768         /* Ignore banks that cannot possibly contain a legal VP index. */
1769         var_cnt = min_t(u16, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS);
1770
1771         if (hc->fast) {
1772                 /*
1773                  * Each XMM holds two sparse banks, but do not count halves that
1774                  * have already been consumed for hypercall parameters.
1775                  */
1776                 if (hc->var_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - consumed_xmm_halves)
1777                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1778                 for (i = 0; i < var_cnt; i++) {
1779                         int j = i + consumed_xmm_halves;
1780                         if (j % 2)
1781                                 sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
1782                         else
1783                                 sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
1784                 }
1785                 return 0;
1786         }
1787
1788         return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks,
1789                               var_cnt * sizeof(*sparse_banks));
1790 }
1791
1792 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
1793 {
1794         struct kvm *kvm = vcpu->kvm;
1795         struct hv_tlb_flush_ex flush_ex;
1796         struct hv_tlb_flush flush;
1797         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1798         u64 valid_bank_mask;
1799         u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1800         bool all_cpus;
1801
1802         /*
1803          * The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the
1804          * valid mask is a u64.  Fail the build if KVM's max allowed number of
1805          * vCPUs (>4096) would exceed this limit, KVM will additional changes
1806          * for Hyper-V support to avoid setting the guest up to fail.
1807          */
1808         BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
1809
1810         if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
1811             hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
1812                 if (hc->fast) {
1813                         flush.address_space = hc->ingpa;
1814                         flush.flags = hc->outgpa;
1815                         flush.processor_mask = sse128_lo(hc->xmm[0]);
1816                 } else {
1817                         if (unlikely(kvm_read_guest(kvm, hc->ingpa,
1818                                                     &flush, sizeof(flush))))
1819                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1820                 }
1821
1822                 trace_kvm_hv_flush_tlb(flush.processor_mask,
1823                                        flush.address_space, flush.flags);
1824
1825                 valid_bank_mask = BIT_ULL(0);
1826                 sparse_banks[0] = flush.processor_mask;
1827
1828                 /*
1829                  * Work around possible WS2012 bug: it sends hypercalls
1830                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1831                  * while also expecting us to flush something and crashing if
1832                  * we don't. Let's treat processor_mask == 0 same as
1833                  * HV_FLUSH_ALL_PROCESSORS.
1834                  */
1835                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1836                         flush.processor_mask == 0;
1837         } else {
1838                 if (hc->fast) {
1839                         flush_ex.address_space = hc->ingpa;
1840                         flush_ex.flags = hc->outgpa;
1841                         memcpy(&flush_ex.hv_vp_set,
1842                                &hc->xmm[0], sizeof(hc->xmm[0]));
1843                 } else {
1844                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
1845                                                     sizeof(flush_ex))))
1846                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1847                 }
1848
1849                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1850                                           flush_ex.hv_vp_set.format,
1851                                           flush_ex.address_space,
1852                                           flush_ex.flags);
1853
1854                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1855                 all_cpus = flush_ex.hv_vp_set.format !=
1856                         HV_GENERIC_SET_SPARSE_4K;
1857
1858                 if (hc->var_cnt != hweight64(valid_bank_mask))
1859                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1860
1861                 if (all_cpus)
1862                         goto do_flush;
1863
1864                 if (!hc->var_cnt)
1865                         goto ret_success;
1866
1867                 if (kvm_get_sparse_vp_set(kvm, hc, 2, sparse_banks,
1868                                           offsetof(struct hv_tlb_flush_ex,
1869                                                    hv_vp_set.bank_contents)))
1870                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1871         }
1872
1873 do_flush:
1874         /*
1875          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1876          * analyze it here, flush TLB regardless of the specified address space.
1877          */
1878         if (all_cpus) {
1879                 kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST);
1880         } else {
1881                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
1882
1883                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST, vcpu_mask);
1884         }
1885
1886 ret_success:
1887         /* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
1888         return (u64)HV_STATUS_SUCCESS |
1889                 ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1890 }
1891
1892 static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1893                                  unsigned long *vcpu_bitmap)
1894 {
1895         struct kvm_lapic_irq irq = {
1896                 .delivery_mode = APIC_DM_FIXED,
1897                 .vector = vector
1898         };
1899         struct kvm_vcpu *vcpu;
1900         unsigned long i;
1901
1902         kvm_for_each_vcpu(i, vcpu, kvm) {
1903                 if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1904                         continue;
1905
1906                 /* We fail only when APIC is disabled */
1907                 kvm_apic_set_irq(vcpu, &irq, NULL);
1908         }
1909 }
1910
1911 static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
1912 {
1913         struct kvm *kvm = vcpu->kvm;
1914         struct hv_send_ipi_ex send_ipi_ex;
1915         struct hv_send_ipi send_ipi;
1916         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1917         u64 valid_bank_mask;
1918         u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1919         u32 vector;
1920         bool all_cpus;
1921
1922         if (hc->code == HVCALL_SEND_IPI) {
1923                 if (!hc->fast) {
1924                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
1925                                                     sizeof(send_ipi))))
1926                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1927                         sparse_banks[0] = send_ipi.cpu_mask;
1928                         vector = send_ipi.vector;
1929                 } else {
1930                         /* 'reserved' part of hv_send_ipi should be 0 */
1931                         if (unlikely(hc->ingpa >> 32 != 0))
1932                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1933                         sparse_banks[0] = hc->outgpa;
1934                         vector = (u32)hc->ingpa;
1935                 }
1936                 all_cpus = false;
1937                 valid_bank_mask = BIT_ULL(0);
1938
1939                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1940         } else {
1941                 if (!hc->fast) {
1942                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
1943                                                     sizeof(send_ipi_ex))))
1944                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1945                 } else {
1946                         send_ipi_ex.vector = (u32)hc->ingpa;
1947                         send_ipi_ex.vp_set.format = hc->outgpa;
1948                         send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
1949                 }
1950
1951                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1952                                          send_ipi_ex.vp_set.format,
1953                                          send_ipi_ex.vp_set.valid_bank_mask);
1954
1955                 vector = send_ipi_ex.vector;
1956                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1957                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1958
1959                 if (hc->var_cnt != hweight64(valid_bank_mask))
1960                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1961
1962                 if (all_cpus)
1963                         goto check_and_send_ipi;
1964
1965                 if (!hc->var_cnt)
1966                         goto ret_success;
1967
1968                 if (kvm_get_sparse_vp_set(kvm, hc, 1, sparse_banks,
1969                                           offsetof(struct hv_send_ipi_ex,
1970                                                    vp_set.bank_contents)))
1971                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1972         }
1973
1974 check_and_send_ipi:
1975         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
1976                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1977
1978         if (all_cpus) {
1979                 kvm_send_ipi_to_many(kvm, vector, NULL);
1980         } else {
1981                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
1982
1983                 kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
1984         }
1985
1986 ret_success:
1987         return HV_STATUS_SUCCESS;
1988 }
1989
1990 void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu)
1991 {
1992         struct kvm_cpuid_entry2 *entry;
1993         struct kvm_vcpu_hv *hv_vcpu;
1994
1995         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_INTERFACE, 0);
1996         if (entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX) {
1997                 vcpu->arch.hyperv_enabled = true;
1998         } else {
1999                 vcpu->arch.hyperv_enabled = false;
2000                 return;
2001         }
2002
2003         if (!to_hv_vcpu(vcpu) && kvm_hv_vcpu_init(vcpu))
2004                 return;
2005
2006         hv_vcpu = to_hv_vcpu(vcpu);
2007
2008         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES, 0);
2009         if (entry) {
2010                 hv_vcpu->cpuid_cache.features_eax = entry->eax;
2011                 hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
2012                 hv_vcpu->cpuid_cache.features_edx = entry->edx;
2013         } else {
2014                 hv_vcpu->cpuid_cache.features_eax = 0;
2015                 hv_vcpu->cpuid_cache.features_ebx = 0;
2016                 hv_vcpu->cpuid_cache.features_edx = 0;
2017         }
2018
2019         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO, 0);
2020         if (entry) {
2021                 hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
2022                 hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
2023         } else {
2024                 hv_vcpu->cpuid_cache.enlightenments_eax = 0;
2025                 hv_vcpu->cpuid_cache.enlightenments_ebx = 0;
2026         }
2027
2028         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES, 0);
2029         if (entry)
2030                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
2031         else
2032                 hv_vcpu->cpuid_cache.syndbg_cap_eax = 0;
2033 }
2034
2035 int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
2036 {
2037         struct kvm_vcpu_hv *hv_vcpu;
2038         int ret = 0;
2039
2040         if (!to_hv_vcpu(vcpu)) {
2041                 if (enforce) {
2042                         ret = kvm_hv_vcpu_init(vcpu);
2043                         if (ret)
2044                                 return ret;
2045                 } else {
2046                         return 0;
2047                 }
2048         }
2049
2050         hv_vcpu = to_hv_vcpu(vcpu);
2051         hv_vcpu->enforce_cpuid = enforce;
2052
2053         return ret;
2054 }
2055
2056 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2057 {
2058         bool longmode;
2059
2060         longmode = is_64_bit_hypercall(vcpu);
2061         if (longmode)
2062                 kvm_rax_write(vcpu, result);
2063         else {
2064                 kvm_rdx_write(vcpu, result >> 32);
2065                 kvm_rax_write(vcpu, result & 0xffffffff);
2066         }
2067 }
2068
2069 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2070 {
2071         trace_kvm_hv_hypercall_done(result);
2072         kvm_hv_hypercall_set_result(vcpu, result);
2073         ++vcpu->stat.hypercalls;
2074         return kvm_skip_emulated_instruction(vcpu);
2075 }
2076
2077 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2078 {
2079         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2080 }
2081
2082 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2083 {
2084         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2085         struct eventfd_ctx *eventfd;
2086
2087         if (unlikely(!hc->fast)) {
2088                 int ret;
2089                 gpa_t gpa = hc->ingpa;
2090
2091                 if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2092                     offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2093                         return HV_STATUS_INVALID_ALIGNMENT;
2094
2095                 ret = kvm_vcpu_read_guest(vcpu, gpa,
2096                                           &hc->ingpa, sizeof(hc->ingpa));
2097                 if (ret < 0)
2098                         return HV_STATUS_INVALID_ALIGNMENT;
2099         }
2100
2101         /*
2102          * Per spec, bits 32-47 contain the extra "flag number".  However, we
2103          * have no use for it, and in all known usecases it is zero, so just
2104          * report lookup failure if it isn't.
2105          */
2106         if (hc->ingpa & 0xffff00000000ULL)
2107                 return HV_STATUS_INVALID_PORT_ID;
2108         /* remaining bits are reserved-zero */
2109         if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2110                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2111
2112         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2113         rcu_read_lock();
2114         eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2115         rcu_read_unlock();
2116         if (!eventfd)
2117                 return HV_STATUS_INVALID_PORT_ID;
2118
2119         eventfd_signal(eventfd, 1);
2120         return HV_STATUS_SUCCESS;
2121 }
2122
2123 static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2124 {
2125         switch (hc->code) {
2126         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2127         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2128         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2129         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2130         case HVCALL_SEND_IPI_EX:
2131                 return true;
2132         }
2133
2134         return false;
2135 }
2136
2137 static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2138 {
2139         int reg;
2140
2141         kvm_fpu_get();
2142         for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2143                 _kvm_read_sse_reg(reg, &hc->xmm[reg]);
2144         kvm_fpu_put();
2145 }
2146
2147 static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2148 {
2149         if (!hv_vcpu->enforce_cpuid)
2150                 return true;
2151
2152         switch (code) {
2153         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2154                 return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2155                         hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2156         case HVCALL_POST_MESSAGE:
2157                 return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2158         case HVCALL_SIGNAL_EVENT:
2159                 return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2160         case HVCALL_POST_DEBUG_DATA:
2161         case HVCALL_RETRIEVE_DEBUG_DATA:
2162         case HVCALL_RESET_DEBUG_SESSION:
2163                 /*
2164                  * Return 'true' when SynDBG is disabled so the resulting code
2165                  * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2166                  */
2167                 return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2168                         hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2169         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2170         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2171                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2172                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2173                         return false;
2174                 fallthrough;
2175         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2176         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2177                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2178                         HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2179         case HVCALL_SEND_IPI_EX:
2180                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2181                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2182                         return false;
2183                 fallthrough;
2184         case HVCALL_SEND_IPI:
2185                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2186                         HV_X64_CLUSTER_IPI_RECOMMENDED;
2187         default:
2188                 break;
2189         }
2190
2191         return true;
2192 }
2193
2194 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2195 {
2196         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2197         struct kvm_hv_hcall hc;
2198         u64 ret = HV_STATUS_SUCCESS;
2199
2200         /*
2201          * hypercall generates UD from non zero cpl and real mode
2202          * per HYPER-V spec
2203          */
2204         if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2205                 kvm_queue_exception(vcpu, UD_VECTOR);
2206                 return 1;
2207         }
2208
2209 #ifdef CONFIG_X86_64
2210         if (is_64_bit_hypercall(vcpu)) {
2211                 hc.param = kvm_rcx_read(vcpu);
2212                 hc.ingpa = kvm_rdx_read(vcpu);
2213                 hc.outgpa = kvm_r8_read(vcpu);
2214         } else
2215 #endif
2216         {
2217                 hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2218                             (kvm_rax_read(vcpu) & 0xffffffff);
2219                 hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2220                             (kvm_rcx_read(vcpu) & 0xffffffff);
2221                 hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2222                              (kvm_rsi_read(vcpu) & 0xffffffff);
2223         }
2224
2225         hc.code = hc.param & 0xffff;
2226         hc.var_cnt = (hc.param & HV_HYPERCALL_VARHEAD_MASK) >> HV_HYPERCALL_VARHEAD_OFFSET;
2227         hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2228         hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2229         hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2230         hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2231
2232         trace_kvm_hv_hypercall(hc.code, hc.fast, hc.var_cnt, hc.rep_cnt,
2233                                hc.rep_idx, hc.ingpa, hc.outgpa);
2234
2235         if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2236                 ret = HV_STATUS_ACCESS_DENIED;
2237                 goto hypercall_complete;
2238         }
2239
2240         if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) {
2241                 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2242                 goto hypercall_complete;
2243         }
2244
2245         if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2246                 if (unlikely(hv_vcpu->enforce_cpuid &&
2247                              !(hv_vcpu->cpuid_cache.features_edx &
2248                                HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2249                         kvm_queue_exception(vcpu, UD_VECTOR);
2250                         return 1;
2251                 }
2252
2253                 kvm_hv_hypercall_read_xmm(&hc);
2254         }
2255
2256         switch (hc.code) {
2257         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2258                 if (unlikely(hc.rep || hc.var_cnt)) {
2259                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2260                         break;
2261                 }
2262                 kvm_vcpu_on_spin(vcpu, true);
2263                 break;
2264         case HVCALL_SIGNAL_EVENT:
2265                 if (unlikely(hc.rep || hc.var_cnt)) {
2266                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2267                         break;
2268                 }
2269                 ret = kvm_hvcall_signal_event(vcpu, &hc);
2270                 if (ret != HV_STATUS_INVALID_PORT_ID)
2271                         break;
2272                 fallthrough;    /* maybe userspace knows this conn_id */
2273         case HVCALL_POST_MESSAGE:
2274                 /* don't bother userspace if it has no way to handle it */
2275                 if (unlikely(hc.rep || hc.var_cnt || !to_hv_synic(vcpu)->active)) {
2276                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2277                         break;
2278                 }
2279                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2280                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2281                 vcpu->run->hyperv.u.hcall.input = hc.param;
2282                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2283                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2284                 vcpu->arch.complete_userspace_io =
2285                                 kvm_hv_hypercall_complete_userspace;
2286                 return 0;
2287         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2288                 if (unlikely(hc.var_cnt)) {
2289                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2290                         break;
2291                 }
2292                 fallthrough;
2293         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2294                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2295                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2296                         break;
2297                 }
2298                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2299                 break;
2300         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2301                 if (unlikely(hc.var_cnt)) {
2302                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2303                         break;
2304                 }
2305                 fallthrough;
2306         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2307                 if (unlikely(hc.rep)) {
2308                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2309                         break;
2310                 }
2311                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2312                 break;
2313         case HVCALL_SEND_IPI:
2314                 if (unlikely(hc.var_cnt)) {
2315                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2316                         break;
2317                 }
2318                 fallthrough;
2319         case HVCALL_SEND_IPI_EX:
2320                 if (unlikely(hc.rep)) {
2321                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2322                         break;
2323                 }
2324                 ret = kvm_hv_send_ipi(vcpu, &hc);
2325                 break;
2326         case HVCALL_POST_DEBUG_DATA:
2327         case HVCALL_RETRIEVE_DEBUG_DATA:
2328                 if (unlikely(hc.fast)) {
2329                         ret = HV_STATUS_INVALID_PARAMETER;
2330                         break;
2331                 }
2332                 fallthrough;
2333         case HVCALL_RESET_DEBUG_SESSION: {
2334                 struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2335
2336                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2337                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2338                         break;
2339                 }
2340
2341                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2342                         ret = HV_STATUS_OPERATION_DENIED;
2343                         break;
2344                 }
2345                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2346                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2347                 vcpu->run->hyperv.u.hcall.input = hc.param;
2348                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2349                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2350                 vcpu->arch.complete_userspace_io =
2351                                 kvm_hv_hypercall_complete_userspace;
2352                 return 0;
2353         }
2354         default:
2355                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2356                 break;
2357         }
2358
2359 hypercall_complete:
2360         return kvm_hv_hypercall_complete(vcpu, ret);
2361 }
2362
2363 void kvm_hv_init_vm(struct kvm *kvm)
2364 {
2365         struct kvm_hv *hv = to_kvm_hv(kvm);
2366
2367         mutex_init(&hv->hv_lock);
2368         idr_init(&hv->conn_to_evt);
2369 }
2370
2371 void kvm_hv_destroy_vm(struct kvm *kvm)
2372 {
2373         struct kvm_hv *hv = to_kvm_hv(kvm);
2374         struct eventfd_ctx *eventfd;
2375         int i;
2376
2377         idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2378                 eventfd_ctx_put(eventfd);
2379         idr_destroy(&hv->conn_to_evt);
2380 }
2381
2382 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2383 {
2384         struct kvm_hv *hv = to_kvm_hv(kvm);
2385         struct eventfd_ctx *eventfd;
2386         int ret;
2387
2388         eventfd = eventfd_ctx_fdget(fd);
2389         if (IS_ERR(eventfd))
2390                 return PTR_ERR(eventfd);
2391
2392         mutex_lock(&hv->hv_lock);
2393         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2394                         GFP_KERNEL_ACCOUNT);
2395         mutex_unlock(&hv->hv_lock);
2396
2397         if (ret >= 0)
2398                 return 0;
2399
2400         if (ret == -ENOSPC)
2401                 ret = -EEXIST;
2402         eventfd_ctx_put(eventfd);
2403         return ret;
2404 }
2405
2406 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2407 {
2408         struct kvm_hv *hv = to_kvm_hv(kvm);
2409         struct eventfd_ctx *eventfd;
2410
2411         mutex_lock(&hv->hv_lock);
2412         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2413         mutex_unlock(&hv->hv_lock);
2414
2415         if (!eventfd)
2416                 return -ENOENT;
2417
2418         synchronize_srcu(&kvm->srcu);
2419         eventfd_ctx_put(eventfd);
2420         return 0;
2421 }
2422
2423 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2424 {
2425         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2426             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2427                 return -EINVAL;
2428
2429         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2430                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2431         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2432 }
2433
2434 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2435                      struct kvm_cpuid_entry2 __user *entries)
2436 {
2437         uint16_t evmcs_ver = 0;
2438         struct kvm_cpuid_entry2 cpuid_entries[] = {
2439                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2440                 { .function = HYPERV_CPUID_INTERFACE },
2441                 { .function = HYPERV_CPUID_VERSION },
2442                 { .function = HYPERV_CPUID_FEATURES },
2443                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2444                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2445                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2446                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2447                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
2448                 { .function = HYPERV_CPUID_NESTED_FEATURES },
2449         };
2450         int i, nent = ARRAY_SIZE(cpuid_entries);
2451
2452         if (kvm_x86_ops.nested_ops->get_evmcs_version)
2453                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2454
2455         if (cpuid->nent < nent)
2456                 return -E2BIG;
2457
2458         if (cpuid->nent > nent)
2459                 cpuid->nent = nent;
2460
2461         for (i = 0; i < nent; i++) {
2462                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2463                 u32 signature[3];
2464
2465                 switch (ent->function) {
2466                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2467                         memcpy(signature, "Linux KVM Hv", 12);
2468
2469                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2470                         ent->ebx = signature[0];
2471                         ent->ecx = signature[1];
2472                         ent->edx = signature[2];
2473                         break;
2474
2475                 case HYPERV_CPUID_INTERFACE:
2476                         ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2477                         break;
2478
2479                 case HYPERV_CPUID_VERSION:
2480                         /*
2481                          * We implement some Hyper-V 2016 functions so let's use
2482                          * this version.
2483                          */
2484                         ent->eax = 0x00003839;
2485                         ent->ebx = 0x000A0000;
2486                         break;
2487
2488                 case HYPERV_CPUID_FEATURES:
2489                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2490                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2491                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2492                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2493                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2494                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2495                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2496                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2497                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2498                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2499                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2500
2501                         ent->ebx |= HV_POST_MESSAGES;
2502                         ent->ebx |= HV_SIGNAL_EVENTS;
2503
2504                         ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2505                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2506                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2507
2508                         ent->ebx |= HV_DEBUGGING;
2509                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2510                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2511
2512                         /*
2513                          * Direct Synthetic timers only make sense with in-kernel
2514                          * LAPIC
2515                          */
2516                         if (!vcpu || lapic_in_kernel(vcpu))
2517                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2518
2519                         break;
2520
2521                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2522                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2523                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2524                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2525                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2526                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2527                         if (evmcs_ver)
2528                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2529                         if (!cpu_smt_possible())
2530                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2531
2532                         ent->eax |= HV_DEPRECATING_AEOI_RECOMMENDED;
2533                         /*
2534                          * Default number of spinlock retry attempts, matches
2535                          * HyperV 2016.
2536                          */
2537                         ent->ebx = 0x00000FFF;
2538
2539                         break;
2540
2541                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2542                         /* Maximum number of virtual processors */
2543                         ent->eax = KVM_MAX_VCPUS;
2544                         /*
2545                          * Maximum number of logical processors, matches
2546                          * HyperV 2016.
2547                          */
2548                         ent->ebx = 64;
2549
2550                         break;
2551
2552                 case HYPERV_CPUID_NESTED_FEATURES:
2553                         ent->eax = evmcs_ver;
2554                         ent->eax |= HV_X64_NESTED_MSR_BITMAP;
2555
2556                         break;
2557
2558                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2559                         memcpy(signature, "Linux KVM Hv", 12);
2560
2561                         ent->eax = 0;
2562                         ent->ebx = signature[0];
2563                         ent->ecx = signature[1];
2564                         ent->edx = signature[2];
2565                         break;
2566
2567                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2568                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2569                         ent->eax = signature[0];
2570                         break;
2571
2572                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2573                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2574                         break;
2575
2576                 default:
2577                         break;
2578                 }
2579         }
2580
2581         if (copy_to_user(entries, cpuid_entries,
2582                          nent * sizeof(struct kvm_cpuid_entry2)))
2583                 return -EFAULT;
2584
2585         return 0;
2586 }